In normal circumstances, if your blood sugar levels dip, your liver produces more glucose from stored carbs. However, when you’ve been hitting the Jagerbombs, your liver is otherwise disposed sorting out the after effects.

In these circumstances, your liver struggles to do its normal work, and without a little perk up, your blood sugar levels will drop, making you feel tired and low. Consume some simple carbs for a quick boost. 

Ask the Expert: Refined Carbohydrates vs Unrefined Carbohydrates?

Of course, consuming a decent sized meal before you go out drinking will also help to line your stomach, and prevent hangovers in the first place.